graphics3d - Tabular Dynamic vectors

Writing:

vp = Options[ParametricPlot3D[{t, t, t}, {t, -5, 5}], ViewPoint][[1, 2]];
ParametricPlot3D[{t, t, t}, {t, -5, 5}, ViewPoint -> Dynamic[vp]]
Dynamic[vp]

I get:

and by rotating the mouse the box changes the vector components in real time.

Unfortunately I can not figure out how to store those vectors in a matrix at each rotation made with the mouse.

Thank you.

Answer

You can use the second argument of Dynamic to specify a function that is executed every time the value is changed:

hist = {};
vp = Options[ParametricPlot3D[{t, t, t}, {t, -5, 5}], ViewPoint][[1, 2]];
ParametricPlot3D[{t, t, t}, {t, -5, 5}, 
 ViewPoint ->Dynamic[vp, {Automatic, AppendTo[hist, #] &}]]
Dynamic[vp]
Dynamic[hist]

Now you can e.g. make an animation showing the states of the viewpoint:

Animate[ParametricPlot3D[{t, t, t}, {t, -5, 5}, ViewPoint -> hist[[v]]], {v, 1, Length@hist, 1}]

Note that it seems to evaluate the function twice each time you rotate the plot, each time with a slightly different value. (But that should be more or less eay to filter out.)

Comments

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